Histogram Sequence

http://codeforces.com/gym/102059/problem/J

C++版本一

题解：单调栈+二分

题解PDF

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
#define endl "\n"
#define PL pair<ll,ll>
#define MP make_pair
#define FI first
#define SE second
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=300000+10;
const int M=100000+10;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int n;
ll a[N],w[N],ans[N];
int s[N];
ll l,r;
priority_queue<PL,vector<PL>,greater<PL> >pq;
struct Node{
    ll l,r;
}p[N];
void ddz(){
    int tot=0;
    a[0]=a[n+1]=0;
    s[++tot]=0;
    for (int j=1;j<=n+1;++j){
        ll wid=0;
        while (a[s[tot]]>a[j]){
            p[s[tot]].l=w[s[tot]];
            p[s[tot]].r=wid+1;
            wid+=w[s[tot]];
            --tot;
        }
        s[++tot]=j;
        w[j]=wid+1;
    }
}
ll solve(ll mid){
    ll rk=0;
    for (int j=1;j<=n;++j){
        ll ww=mid/a[j];
        //printf("%I64d %I64d %I64d %I64d %I64d\n",ww,mid,a[s[tot]],wid,w[s[tot]]);
        ll minn=min(p[j].l,p[j].r);
        ll maxn=max(p[j].l,p[j].r);
        if (ww<=minn){
            rk+=ww*(ww+1)/2;
        }else{
            rk+=minn*(minn+1)/2;
            if (ww<=maxn){
                rk+=minn*(ww-minn);
            }else{
                rk+=minn*(maxn-minn);
                ll sum=p[j].l+p[j].r;
                ww=min(ww,sum);
                ll ah=sum-maxn-1;
                ll wh=sum-ww;
                rk+=(ww-maxn)*(ah+wh)/2;
            }
        }
    }
    return rk;
}
void fid(ll pos){
    ll ls=1;
    ll rs=3e14;
    ll rk=0;
    while (ls<=rs){
        ll mid=(ls+rs)>>1;
        rk=solve(mid);
        if (rk<pos)ls=mid+1;
        else rs=mid-1;
    }
    if (rk<pos)rk=solve(ls);
    for (ll j=pos;j<=r&&j<=rk;++j)ans[j-l]=ls;
}
int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    //ios::sync_with_stdio(false);
    //cin.tie(0);
    //cout.tie(0);
    //scanf("%d",&t);
    //while(t--){
    scanf("%d",&n);
    for (int i=1;i<=n;++i)scanf("%I64d",&a[i]);
    scanf("%I64d%I64d",&l,&r);
    ddz();
    fid(l);
    for (int i=1;i<=n;++i){
        ll lim=ans[0]/a[i];
        pq.push(MP((lim+1)*a[i],i));
    }
    int pos=0;
    for (int i=1;i<=r-l;++i)if(!ans[i]){pos=i-1;break;}
    while (!pq.empty()&&!ans[r-l]){
        PL fp=pq.top();
        pq.pop();
        int j=fp.SE;
        ll ww=fp.FI/a[j];
        ll ns=fp.FI;
        ll minn=min(p[j].l,p[j].r);
        ll maxn=max(p[j].l,p[j].r);
        ll rk=0;
        if (ww<=minn){
            rk=ww;
        }else{
            if (ww<=maxn){
                rk=minn;
            }else{
                ll sum=p[j].l+p[j].r-1;
                rk=max(sum-ww+1,0ll);
            }
        }
        for (int i=pos+1;i<=r-l&&i<=pos+rk;++i)ans[i]=ns;
        pos+=rk;
        cout<<pos<<endl;
        if (rk!=0) pq.push(MP(fp.FI+a[fp.SE],fp.SE));for (int i=0;i<=r-l;++i)printf("%3I64d%c",ans[i]," \n"[i==r-l]);
    }

    //}

#ifdef DEBUG
	printf("Time cost : %lf s\n",(double)clock()/CLOCKS_PER_SEC);
#endif
    //cout << "Hello world!" << endl;
    return 0;
}